Spherical Lithium Deposition Enables High Li‐Utilization Rate, Low Negative/Positive Ratio, and High Energy Density in Lithium Metal Batteries

Abstract

Lithium metal battery promises an attractively high energy density. A high Li‐utilization rate of Li metal anode is the prerequisite for the high energy density and avoiding a huge waste of the Li resource. However, the dendritic Li deposition gives rise to “dead Li” and parasitic interfacial reactions, resulting in a low Li utilization rate. Herein, Li deposition is regulated to spherical Li by designing an MXene host with an egg‐box structure, suitable curvature, and continuous gradient lithiophilic structure. Because the spherical Li greatly reduces the interfacial side reactions and avoids the formation of dead Li, the Li anode affords a high plating/stripping efficiency. Furthermore, the gradient lithiophilic design results in a bottom‐up growth of the spherical Li within the host, safely away from the separator. Thus, the spherical Li anode realizes a long life of >3000 h with a high Li‐utilization rate of >90%, stable cycling in full cells at an areal capacity up to 5 mAh cm−2 with a low negative/positive ratio of 0.8, which is critical for high energy density. Such spherical deposition highlights the critical role of the morphological control of alkali metals and provides a viable method to build practical high‐energy metal batteries.

Stabilizing a Li1.3Al0.3Ti1.7(PO4)3/Li metal anode interface in solid-state batteries with a LiF/Cu-rich multifunctional interlayer

“…The spherical lithium deposition guided by the lithiophilic interface layer can greatly reduce the side reaction of the interface, avoid the formation of dead lithium, and effectively improve the utilization rate of the lithium anode. 45 These results indicate that the introduction of a CuF 2 composite layer can inhibit dendrite growth and guide uniform Li deposition, verifying the enhanced chemical/electrochemical stability of the Li/CuF 2 @LATP interface.…”

Recent advances in solid-state lithium batteries based on anode engineering

“…(3) Densifying SSEs and optimizing external stack pressure: optimization of synthesis conditions and controlling morphology or compositions are effective ways to densify SSEs and create uniform interfaces LMA/SSE with fewer voids and cracks. Optimal stack pressure enables good physical contact and prevents void generation during stripping [151].…”

Introduced Hierarchically Ordered Porous Architecture on a Separator as an Efficient Polysulfide Trap toward High-Mass-Loading Li–S Batteries

“…To address these issues, there are four main strategies in the realm of research: the fabrication of sulfur cathode structure, the modification of separators, the development of novel electrolytes, and the protection of lithium anode . Among them, separator modification for Li–S batteries is regarded as a facile and effective measurement, which involves constructing a functional interlayer between the cathode and the separator to alleviate the shuttle effect of LiPSs which cannot be prevented by commercial polypropylene (PP) separators. − Introducing carbon materials, such as graphene, carbon nanotubes, hollow carbon spheres, Super P, MXene, − quantum dots, and carbon aerogels, has been a prevalent approach in the fabrication of separator interlayers in Li–S batteries and regulation of lithium-ion dynamics, whereas the spatial architecture and adsorption properties of materials impose constraints on their ability to suppress the shuttle effect, and regrettably, significant functional deterioration occurs when the cathode exhibits a high sulfur loading. Moreover, the coverage of separator pores hinders the transport of lithium ions, resulting in sluggish LiPS conversion kinetics.…”